Private Investment Funds earn their keeps by offering their expertise to the super rich. They named a price and the private investors would decide who to park their money with. If the Funds could not perform, the investors would pull out and look for better performance Funds to invest their money. There is fierce competition for customers in terms of returns on investment and cost of investment.
Sovereign Wealth Funds are a totally different kettle of fish. They acquired funds by involuntary means, mostly nation's reserves or citizens' savings to invest. It is like, here is the money, go and do what you like with it. They, the fund managers, decide who would be the fund managers, how much to pay themselves.
The investors are passive, ie country's reserves plus CPF money in Singapore's case. Actually all the money belongs to the people one way or another. The glaring difference in SWF and PIF is that in the former, the owners of the fund did not have a say in anything. The owners cannot appoint who to be the fund managers, who should be hired or fired if not performing. They cannot decide how much to pay or reward the fund managers or to reduce their pay for bad performance. They cannot fire the fund managers. They are totally not involved, not informed, kept in the dark. And in Singapore's case, they did not know how much of their money are invested in the funds and did not know how much the funds made or lost. They are told by the fund managers what the fund managers wanted them to know and have to take them at good faith.
Another glaring fact of SWF is that many of the owners of the funds are barely able to pay for their medical bills as their savings are stuck and subject to the rules of their savings fund. In other words many of the owners are poor people or relatively poor.
On the other hand the fund managers are completely independent of the owners of the funds and are free to do whatever they want with the funds, how much to pay and reward themselves. Thus, the fund managers are extremely rich and comfortable and could party all the time, like Napoleon and his 2 legs are good, 4 legs are better friends in the Animal Farm.
Life is like having a ball for the fund managers in SWF. The fund managers are rich but the owners are poor. The owners of the money cannot sack them or move out their money. Where got such favourable employment terms on earth? Now you know why the owners are getting poorer and the fund managers, the self appointed employees, are laughing all the way to the banks. When they lose, it is OPM. Anyone to check and verify the accounts, whether it is profit or loss?
Where is the accountability? The owners of the money just have to trust them and what they say. How much of the profits, if any, goes to the fund managers? How much goes to the owners of the money?